One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for San Dimas can be looked at to estimate when to plant pennyroyal.

Planting Calendar for Pennyroyal

Frost tolerance for pennyroyal:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since pennyroyal do well in cold you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pennyroyal in San Dimas is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant pennyroyal and expect a good harvest is probably October. If you wait any later than that and your pennyroyal may not have a chance to fully mature. Starting your pennyroyal indoors is a great way to get them started a little bit earlier.

Last Frost Date

In San Dimas the average date of last frost happens on January 31. In the coldest months of winter you can expect an average low temperature of 30°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for San Dimas and it can change quite a bit from year to year. Half of the time in San Dimas last frost occurs after January 31 so make sure that you are prepared to protect your pennyroyal in the event of one of those late frosts.

USDA Zone Info for San Dimas

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in San Dimas

You may be interested in your other planting guides for San Dimas.